Electric switch.



No. 688,282. Patented 080.10, I90l.

- c. A. aenssmom.

ELEGTRIOSVHTCHF (Application filed July 21, 1900.)

(No Model.)

WITNESSES: v I I INYENTQR 4 20 (M @xae @Myafi 'v 1 BY a M 2. 6%

I ATTORNEY- UNITED STATES PATENT OFFICE.

CARL AXEL BERGSTROM, OF NEW YORK, N. Y., ASSIGNOR OF ONE-HALF TO MARTIN SINGER, OF NEW YORK, N. Y.

ELECTRIC SWITCH.

SPECIFICATION forming part Of Letters Patent NO. 688,282, dated. December 10, 1901.

Application filed July 21, 1900. Serial No. 24,371. (No model.)

To all whom it may concern:

Be itknown that I, CARL AXELBERGSTROM, a citizen of the United States of America, and a resident of the city, county,and State of New York, have invented certain new and useful Improvements in Electric Switches, of which the following is a specification.

My invention relates to improvements in electric switches, and particularly to improvements in switches for electric-lighting purposes.

My invention consists in certain novel details of construction and combination of parts, as herein set forth.

ondly, to reduce the size of the switch as a whole; thirdly, to so construct the same that access to the interior thereof shall be a matter of easy accomplishment, and, lastly, to construct a switch which shall consist of but few parts and that liability of such parts getting out of order shall be reduced to a minimum.

I will now proceed to describe an electric switch embodying myinvention and will then point out the novel features in the claim.

In the drawings, Figure 1 is an outside View of an electric switch embodyingmy invention, the said view being made about full size of the switch. Fig. 2 represents a cen-' 5 is a transverse sectional view of two semi-' globular shell members employed and showing them removed from the other parts of the device. Fig. 6 is a detail View, partly in section and partly in side elevation, of a bayonet-joint connection employed. Fig. 7 represents a partial horizontal section taken on the line 7 7 of Fig. 2.

The objects of my invention are, first, to simplify the construction of an electric switchv suitable for electric-lighting purposes; sec-' the stationary contact-plate.

Similar reference characters designate corresponding parts in the several views.

Reference character 8 designates a casing, which may be made of metal and which is provided with internally-screw-threaded ex .tensions, such as are suitable for connecting the switch with other portions of an electriclight bracket. The casing 8 has a cylindrical bore, and within the bore, at the lower side thereof, is secured a terminal support 9, which is preferably com posedof an insulating material, such as fiber or vulcanite. Two stationary contact plates or terminals 10 and 11 are secured to the support 9, as by screws, as shown, and binding-screws 12 are provided in electrical connection therewith, to which may be secured the ends of leading-in wires.

A movable contact-plate is provided, which is pivotally mounted at 13in the casing 8 and which comprises three arms 14, 15, and 16. The arm 14 carries a bridge-piece 17, which is insulated therefrom and which is adapted in one position of the movable contact-plate to form a bridge between the stationary contact-plates and to electrically connect the same. The arm 16 bears against a leaf-spring 18, the tendency of which is to rock the said contact-plate upon its pivotal support and to carry the bridge-piece 17 out of contact with The third arm 15 extends upwardly in a slot provided therefor in a cylindrical hub 19 of the casing 8 and bears at its end against an operatingcam 20.

The operating-cam 20 is secured upon a spindle 21, to which is secured an operatinghandle 22. The operating-handle 22, spindle '21, and cam 20'are retained in their proper relative positions to the casing by means of from points at the smallest diameter to points I at the largest diameter of the said cam, portions which are substantially arcs of circles at the points of the greatest diameter of the said cam, two small recesses arranged in such parts as are substantially arcs of circles, and two portions which quickly drop from points in the largest diameter of the said cam to points in the smaller diameter thereof.

As shown in the drawings, the various parts of the switch are in the positions which they assume when contact is broken between the stationary contact-plates 10 and 11. To close contact, the operating-spindle will be par? tially rotated, and the cam 20 will be forced around in the direction of the arrow in Fig. 7, and will thereby force the rising portion of the cam against the arm 15 of the movable plate until the said movable contact-plate is rocked upon its support to an extent sufficient to force the bridge-piece 17 between the stationary contact-plates l0 and 11. After contact between these plates has been socurely made the end of the arm 15 of the stationary contact-plate will drop into the recess in the cam, which is in the largest diameter thereof and which at that time will have been moved to such a position as to be ready to receive it. This recess or notch will hold the cam and the contact-plate stationary in the positions to which they have been moved until such time as they shall be released by the fu rther forcible rotation of the operating-spindle 21. Such further rotation will be given to the operating-spindle when it is desired to electrically disconnect the contacts 10 and 11, and upon such further rotation, by reason of the peculiarconfiguration of the cam, the said movable contact-plate will be caused to be quickly released, and the action of the spring 18 will rotate the said movable contact-plate upon its pivotal support, and thereby move the bridge-piece 17 out of contact with the said stationary contact-plates. The quickness of movement of these plates will prevent sparking between the bridge-piece 17 and the stationary contact-plate.

I have provided two semiglobular shell members 21 and 25 for the purpose of inclosing the mechanism that is within the bore of the casing 8. One of these semiglobular shell members is provided with a rib which is arranged to fit over the edge of the other semiglobular shell member and by which ajoint may be effected between the said members which is practically impervious to dust.

One of the internally screw-threaded extensions of the casing 8 has fitted to it a ring 26. The ring 26 has a bayonet-joint connection between it and the said extension, as shown more clearly in Fig. 6. The bayonet-joint connection is so arranged that the ring 26 may be locked in the position in which it is shown in Figs. 3, 4, and 6 upon its support, but that upon the partial rotation of the same the said ring may be moved for a short distance outwardly. When the said ring 26 is so rotated upon its support and so moved out wardly, the semiglobular shell members 24 and 25 may be removed from and replaced into position. The shell members 24 and 25 when in position may be securely locked in such position by the pressing home and partial rotation of the ring 26 in the opposite direction.

The foregoing construction permits of the ready removal of the shell members when desired for the purpose of inspecting the interior of the switch and for the equally ready replacing of the same. The construction of the upper parts is such that after access has been obtained thereto by the removal of the shell all the said parts can be simply and easily removed and replaced. The support 9 and the two stationary contact-plates 10 and 11 may be moved by the removal of a single screw 30, which secures the same to the casing 8. The movable contact-plate and its spring may be removed by the removal of its pivot-pin 13, and the operating-spindle handle and cam may be removed by the removal of the cap 19. Thus after the said shell members have been removed all the other parts of the device may be removed in three operations.

9 What I claim is The combination with a casing 8 having a hub 19, a hollow bore and hollow threaded bosses or extensions leading into said bore, said casing forming the supporting-frame of a bracket-arm switch, of two stationary contact-plates 10 and 11 secured within the 1101- low bore of said casing, and insulated from each other,-a rotatable operating-spindle 21 mounted in the hub 19 of said casing, and retained in position therein by a cap 23, said rotatable operating-spindle having a laterally-arranged cam projection 20 thereon, and disposed between the face of the boss 19 and the inner face of the cap 23, a spring-actuated movable contact-plate pivotally mounted in said casing at right angles axially to the axis of rotation of the operating-spindle, and having a movement in a plane substantially at right angles to a line passing through the bosses or extensions of said casing, the said contact-plate having three arms, radiating in different directions from its axis, one of said arms provided with a bridge-piece, another of said arms bearing against, and actuated by, a spring, and the third of said arms passing through a slot in the hub 19, and adapted to engage with, and be operated by, the cam projection carried by the said operating-spindle.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CARL AXEL BERGSTROM.

\Vitnesses:

EDW. B. HAWKINS, C. F. CARRINGTON. 

